This application claims Paris Convention priority of DE 198 48 452.6 filed Oct. 21, 1998 the complete disclosure of which is hereby incorporated by reference.
The invention concerns a device for the insertion of products into a packaging container in a packaging machine with an insertion plunger guided along a certain path parallel to the products and a cover element which can be pre-positioned above a product by means of a first displacement control and which can be lowered onto the product by means of a second displacement control, wherein the insertion plunger and the cover element exercise a common insertion motion to introduce the product into the container.
Devices of the above mentioned kind are generally utilized in continuously operating packaging machines equipped e.g. with a product chain upon which the products to be packaged (tubes, bottles or a stack of blister pack strips) are transported. Containers, e.g. folded boxes, are guided parallel to the product chain for insertion of the product, optionally together with a brochure. This is effected with the assistance an insertion plunger which is likewise moved in the main transport direction parallel to the product chain by means of a chain transporter to carry out an insertion displacement perpendicular to the main transport direction.
Particularly for insertion of a stack of blister pack strips, it is necessary to slightly press the stack together and stabilize it prior to insertion. Toward this end, DE 43 061 731 proposes a cover element which is displaced above the stack of package strips in raised alignment and then lowered onto the pack. The cover element, together with the insertion plunger, then carry out an insertion motion in mutual cooperation, wherein the cover element seats on the stack of pack strips until they are received within the packaging container.
It is thereby important that the displacement dependence of the cover element be precisely tuned to the size of the products to be inserted. If the cover element prematurely seats on the stack of pack strips and is displaced under pressure on the upper side thereof before the stack is supported at its sides, the upper pack strip can be displaced as a result of which the desired stacked configuration is lost and the stack can no longer be inserted into the container. The height of the cover strip and its lowering and raising displacements are controlled by means of a curved path guide formed in an adjustable frame member in which a curve roller, borne for rotation about a horizontal axis, travels, to determine the height of the cover element. When a vertically lowermost section of the curved path is reached, the curve roller is lowered along with the cover element. In a vertically rising section of the curved path guide, the cover element is correspondingly lifted via the curve roller.
When the product to be packaged is changed, the overall height of the frame member in which the control curve is formed must be raised or lowered. This procedure is tedious, time consuming, and therefore expensive.
It is the underlying purpose of the invention to create a device of the above mentioned kind which guarantees a precise seating of the cover element and facilitates a simple reconfiguration to differing product formats.
This purpose is achieved in accordance with the invention with a device for insertion of products into a packaging container in that the second displacement control comprises a substantially vertical control surface and an element seating on the control surface for horizontal adjustment thereby, wherein the horizontal adjustment motion of the element can be transformed via a transformation device into the vertically lowering motion of the cover element.
The underlying concept of the invention is to deliver the cover element to the products, i.e. align it above the product stack and to effect the lowering of the cover element onto the product stack using two independent displacement controls. Since a format change normally requires only a change in the height of the product stack, whereas the delivery motion remains at least approximately constant, a format change only requires intervention in the second displacement control.
The separation between delivery and pre-positioning of the cover element and the lowering motion allows both displacements to be optimized, independent of each other, to the products to be packaged as well as to the structural boundary conditions within the machine, as a result of which a high functional reliability is imparted to the machine.
In accordance with the invention, the lowering and raising of the cover element is not effected by a vertically changing dependence of a horizontal control surface, rather by means of a horizontally changing dependence of a vertical control surface. The vertical control surface causes the element seating on the surface, which could be a curve roller borne for rotation about a vertical axis, to be horizontally adjusted. This horizontal adjustment of the curve roller is mapped by a transformation device, in particular in the form of a simple transfer system, into a vertically lowering and raising displacement of the cover element. This configuration has the advantage that a format change only requires displacement of the control surface in the machine in a horizontal direction along a guide. This is substantially simpler for the operator than is a vertical raising of an entire section of the frame member. Moreover, the control surface can be sidewardly removed from the machine and exchanged.
A particularly simple structural configuration of the control surface is given when the surface is fashioned on an adjustment plate which can be displaced to effect a format change, and which has a surface or surface structure engaged by the curve roller. A format change then only requires an adjustment of the adjustment plate.
In order to guarantee a secure seating of the curve roller on the control surface, it should be pre-tensioned against the control surface using a spring.
It has turned out to be particularly advantageous when the transformation device comprises a slanted linear guide which can be preferentially formed by a guide rod tilted with respect to the horizontal and vertical.
A preferred embodiment of the invention provides that the second displacement control comprises a control element which, can be vertically adjusted together with the cover element as a unit and which can be horizontally displaced relative to the cover element, wherein the curve roller seating on the control surface is borne on the control element. The substantially horizontal delivery motion of the cover element into the position above the product stack can thereby be effected without having to move the control element, since this element can be displaced horizontally relative to the cover element. The control element controls the vertical lowering of the cover element and engages, towards this end, the control surface via the curve roller. The diagonal linear guide allows the control element to follow the horizontal shape of the control surface or of the adjustment plate to thereby simultaneously experience a vertical displacement as a result of which the initial position for the lowering motion of the control member and thereby of the cover element can be changed. The relationship between the horizontal and vertical adjustment motion of the control element is given by the angle of the slanted guide rod, wherein an angle of 45xc2x0 is preferentially provided so that the two displacement fractions are equal.
The first displacement control which controls the delivery and pre-positioning of the cover element, comprises a forward insertion carriage which can be displaced towards the product, which can be moved via a control curve, and which bears a vertical guide rod on which the cover element and the control element are borne in a vertically adjustable fashion. The cover element should seat in the above mentioned fashion from above on the product or the stack of pack strips and load same with a suitable, normally small amount of pressure.
This pressure can either be effected by the intrinsic weight of the cover element or, optionally, the cover element can be pre-tensioning via a spring when seating on the products.
Additional features and details of the invention can be extracted from the following description of an embodiment with reference to the drawing.